Conventional pivot motors are used in hair clippers because they produce reciprocating motion that vibrates a cutting blade to cut hair. Such pivot motors have an armature with a drive arm on one end, a magnetic assembly on the opposite end, and a pivot between the drive arm and the magnetic assembly. A stator located adjacent the magnetic assembly produces magnetic flux that drives the armature back and forth, in turn oscillating a reciprocating blade to cut hair. The power transmitted to the reciprocating blade is affected by the efficiency of the magnetic circuit and flux transfer of energy between the stator and the magnetic assembly.
In a known magnetic assembly, shown in FIGS. 5A and 5B, an alternating current passing through a coil 502 generates magnetic flux that passes through laminations 504. The flux passes through a magnetic assembly 506 in an armature (not shown in FIGS. 5A and 5B). The flux draws the magnetic assembly to the position shown in FIG. 5A during one portion of the alternating current cycle.
The magnetic assembly 506 includes two magnets 508, 510 arranged at an oblique angle to each other. A V-shaped flux bridge 512 spans the two magnets, which increases power and efficiency. The present invention further improves efficiency and further increases power transfer in such pivot motors.
Accordingly, one object of this invention is to provide new and improved pivot motors.
Another object is to provide new and improved pivot motors having improved efficiency and better power transfer from the stator to the magnetic assembly in the armature.
Still another object is to provide new and improved hair clippers that are driven by a pivot motor.
Yet another object is to provide new and improved hair clippers having more efficient and more powerful pivot motors.